/* Alloy Analyzer 4 -- Copyright (c) 2006-2009, Felix Chang
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify,
 * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

package edu.mit.csail.sdg.alloy4compiler.ast;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import edu.mit.csail.sdg.alloy4.Pos;
import edu.mit.csail.sdg.alloy4.ConstList;
import edu.mit.csail.sdg.alloy4.JoinableList;
import edu.mit.csail.sdg.alloy4.Err;
import edu.mit.csail.sdg.alloy4.ErrorType;
import edu.mit.csail.sdg.alloy4.ErrorWarning;
import static edu.mit.csail.sdg.alloy4compiler.ast.Type.EMPTY;

/** Immutable; represents an illegal pred/fun call.
 *
 * <p> <b>Invariant:</b>  this.type==EMPTY && this.errors.size()>0
 */

public final class ExprBadCall extends Expr {

    /** The function. */
    public final Func fun;

    /** The unmodifiable list of arguments. */
    public final ConstList<Expr> args;

    /** The extra weight added to this node on top of the combined weights of the arguments. */
    public final long extraWeight;

    /** Caches the span() result. */
    private Pos span=null;

    /** {@inheritDoc} */
    @Override public Pos span() {
        Pos p=span;
        if (p==null) {
            p=pos.merge(closingBracket);
            for(Expr a:args) p=p.merge(a.span());
            span=p;
        }
        return p;
    }

    /** {@inheritDoc} */
    @Override public void toString(StringBuilder out, int indent) {
        if (indent<0) {
            out.append(fun.label).append('[');
            for(int i=0; i<args.size(); i++) { if (i>0) out.append(", "); args.get(i).toString(out,-1); }
            out.append(']');
        } else {
            for(int i=0; i<indent; i++) { out.append(' '); }
            out.append("ExprBadCall: ").append(fun.isPred?"pred ":"fun ").append(fun.label).append('\n');
            for(Expr a:args) { a.toString(out, indent+2); }
        }
    }

    /** Constructs an ExprBadCall object. */
    private ExprBadCall(Pos pos, Pos closingBracket, boolean ambiguous, Func fun, ConstList<Expr> args, JoinableList<Err> errors, long extraWeight, long weight) {
        super(pos, closingBracket, ambiguous, EMPTY, 0, weight, errors);
        this.fun=fun;
        this.args=args;
        this.extraWeight=extraWeight;
    }

    /** Constructs an ExprBadCall object. */
    public static Expr make(final Pos pos, final Pos closingBracket, final Func fun, ConstList<Expr> args, long extraPenalty) {
        if (extraPenalty<0) extraPenalty=0;
        if (args==null) args=ConstList.make();
        long weight = extraPenalty;
        boolean ambiguous = false;
        JoinableList<Err> errors = emptyListOfErrors;
        for(Expr x: args) {
            weight = weight + x.weight;
            ambiguous = ambiguous || x.ambiguous;
            errors = errors.make(x.errors);
        }
        if (errors.isEmpty()) {
            StringBuilder sb=new StringBuilder("This cannot be a correct call to ");
            sb.append(fun.isPred?"pred ":"fun ");
            sb.append(fun.label);
            sb.append(fun.count()==0 ? ".\nIt has no parameters,\n" : ".\nThe parameters are\n");
            for(ExprVar v:fun.params()) {
                sb.append("  ").append(v.label).append(": ").append(v.type).append('\n');
            }
            sb.append(args.size()==0 || fun.count()==0 ? "so the arguments cannot be empty.\n" : "so the arguments cannot be\n");
            int n = fun.count();
            for(Expr v: args) {
                if (n==0) break; else n--;
                sb.append("  ");
                v.toString(sb, -1);
                sb.append(" (type = ").append(v.type).append(")\n");
            }
            errors = errors.make(new ErrorType(pos, sb.toString()));
        }
        return new ExprBadCall(pos, closingBracket, ambiguous, fun, args, errors, extraPenalty, weight);
    }

    /** {@inheritDoc} */
    public int getDepth() {
        int max = 1;
        for(Expr x: args) { int tmp=x.getDepth(); if (max<tmp) max=tmp; }
        return 1 + max;
    }

    /** {@inheritDoc} */
    @Override public Expr resolve(Type t, Collection<ErrorWarning> warns) { return this; }

    /** {@inheritDoc} */
    @Override final<T> T accept(VisitReturn<T> visitor) throws Err { return visitor.visit(this); }

    /** {@inheritDoc} */
    @Override public String getDescription() { return "<b>error</b> (parser or typechecker failed)"; }

    /** {@inheritDoc} */
    @Override public List<? extends Browsable> getSubnodes() { return new ArrayList<Browsable>(0); }
}
